Battery systems having a plurality of battery cells are used, in particular, as energy stores for a drive of electric and hybrid vehicles. In order to ensure an optimum function of the energy store, it is necessary to keep the temperature of the battery cells in a desired operating range. In order to prevent the operating temperature being exceeded and/or undershot, active or passive temperature-control systems are used. The use of liquid temperature-control medium with a high thermal capacity has proven itself particularly, which temperature-control medium is guided along the battery cells in a satisfactorily thermally conducting manner, in a heat exchanger.
It is a problem, however, in the case, for example, of an accident of a vehicle which is equipped in this way. Leaks, and therefore, the discharge of the temperature-control medium from the cooling element may occur. The temperature-control medium may then pass into direct contact with the battery cells and, as a result of its conductivity, may cause a short circuit, for example.
A battery system is known from German Patent Publication No. DE 10 2010 010 844 A1. The battery system which is disclosed therein describes a storage module for voltage supply, in particular of a vehicle with a number of storage cells which in each case have a first and a second connector terminal of different polarity and a valve. The storage cells are connected electrically via the connector terminals to form the storage module. An internal pressure which is present in a storage cell may be dissipated and electrolyte may be discharged from the storage cell via a respective valve.
The storage cells of the storage module which is described have a valve in the form of a predetermined break point. This predetermined break point makes it possible for excess electrolyte to be discharged from the interior of the storage cell in the case of ageing of the storage cell. Since the electrolyte which is used in storage cells is usually electrically conducting, this may lead to short-circuits within the storage module and the function of the entire storage module may no longer be ensured.
Conventional devices are not suitable for binding large amounts of temperature-control medium which are discharged from a temperature-control system in the interior of a closed battery housing in the case of damage, and thus, are not suitable for effectively preventing damage to battery systems and cells.